| Campkin Limited | Administrative & support | 2007 |
| Captain Webb (Wellington) Limited | Hospitality | 2015 |
| Cares Fire Safety Ltd | Public administration | 2023 |
| Carman Medical Services Limited | Health & social care | 2019 |
| Cast Iron Books Ltd | Information & communication | 2020 |
| CB Brokers Limited | Financial services | 2020 |
| Ccraj Ltd | Wholesale & retail | 2019 |
| Channel Gateway Limited | Construction | 2024 |
| Charis Global Ltd | Health & social care | 2017 |
| Charles Bridge Prague Ltd | Information & communication | 2026 |
| Charles Edis Limited | Professional & scientific | 2011 |
| Chase Consulting Ltd | Professional & scientific | 2013 |
| Chelston Car Storage Limited | Wholesale & retail | 2019 |
| Chelston Holdings (SW) Ltd | Financial services | 2024 |
| Chelston Park Nursing and Residential Home Limited | Health & social care | 2000 |
| Chelston Properties (South West) Limited | Real estate | 2017 |
| Chiltern Holdings Limited | | 2023 |
| Chkd Limited | Arts & recreation | 2013 |
| Chris Bolton Ltd | Professional & scientific | 2025 |
| Chris Mitchell Financial Planning Limited | Professional & scientific | 2020 |
| Chris Powell Carpentry Ltd | Construction | 2025 |
| Christopher Milton Executive Coaching Limited | Professional & scientific | 2022 |
| Churchbury Securities Ltd | Real estate | 1987 |
| City Dapper Dogs Ltd | Wholesale & retail | 2025 |
| CJ Systems Limited | Information & communication | 2010 |
| Cjsa Consulting Ltd | Information & communication | 2026 |
| CL International Ltd | Administrative & support | 2015 |
| Clan Farm Properties LLP | | 2024 |
| Classic Glazing South West Ltd | Construction | 2026 |
| Clean NRG Solar Solutions Limited | Construction | 2025 |
| Cleanology Cleaning Services Ltd | Administrative & support | 2021 |
| Cleanwright Carpets Ltd | Administrative & support | 2023 |
| Clear View Surveyors Ltd | Professional & scientific | 2024 |
| Clifton Contracting Ltd | Construction | 2019 |
| Clipfix Ltd | Construction | 2018 |
| Cloud Chasers Ltd | Wholesale & retail | 2025 |
| Cloudburst Consulting Limited | Information & communication | 1997 |
| Clyffe Farms(Tincleton)Limited | Agriculture & fishing | 1972 |
| CMC (South West) Limited | Manufacturing | 2002 |
| Coactivity at Work Limited | Professional & scientific | 2002 |
| Coast IOW Ltd | Construction | 2014 |
| Coate&Co Properties Ltd | Construction | 2026 |
| Cockle Beach Ltd | Hospitality | 2020 |
| Cognet AI Limited | Information & communication | 2025 |
| Cogo Connecting Good | | 2017 |
| Cole & Davis Enterprises Ltd | Professional & scientific | 2015 |
| Combined Building & Decorating Limited | Construction | 2024 |
| Commercial Investments (SW) Limited | Real estate | 2024 |
| Commercial Machinery Auctions Ltd | Manufacturing | 2023 |
| Community Counselling CIC | Education | 2018 |
| Community Health International (C.H.I) Limited | Health & social care | 2005 |
| Compass Educational Psychology Ltd | Health & social care | 2023 |
| Complete Property Development SW Ltd | Construction | 2025 |
| Complete Roofing & Building Solutions Ltd | Construction | 2019 |
| Complete Trading (SW) Ltd | Wholesale & retail | 2013 |
| Concept Project Management Ltd | Information & communication | 2018 |
| Construction & Utility Solutions Partnerships Limited | Professional & scientific | 2011 |
| Contractor Connect Ltd | Administrative & support | 2024 |
| Control Metrix Ltd | Wholesale & retail | 2024 |
| Converga - UK Branch of Datam | | 2009 |
| Conway Cladding Limited | Construction | 2011 |
| Conway Property Limited | Real estate | 2020 |
| Cooke Keys Ltd | Real estate | 2026 |
| Coopers Window Cleaning Ltd | Administrative & support | 2013 |
| Cordy Connect Electrical Services Limited | Construction | 2025 |
| Corpus Properties Limited | Professional & scientific | 2005 |
| Cottage to Castle SW Ltd | Wholesale & retail | 2022 |
| County Flowers Ltd | Wholesale & retail | 2011 |
| County Roofing Contractors Limited | Construction | 2004 |
| Court Healthcare Limited | Health & social care | 1998 |
| Court Place Barns Management Services Limited | Households | 2003 |
| Courtship Limited | Construction | 1987 |
| Covenant Care Limited | Health & social care | 2013 |
| Covenant Care Support LLP | | 2004 |
| COW Recovery Limited | Wholesale & retail | 2025 |
| Coxmar Ltd | Professional & scientific | 2015 |
| Crafting Butterfly and Friends Ltd | Wholesale & retail | 2026 |
| Craigbeth Engineering Limited | Professional & scientific | 2007 |
| Create Landscaping Limited | Administrative & support | 2009 |
| Crewdogs Event Crewing Ltd | Construction | 2023 |
| Crpg Response CIC | Public administration | 2026 |
| Cryogene Laboratories Ltd | Professional & scientific | 2026 |
| Cube Direct Ltd | Wholesale & retail | 2022 |
| Culm Cooling Refrigeration & Electrical Services Limited | Manufacturing | 2013 |
| Culm Valley Poultry Limited | Agriculture & fishing | 2007 |
| Curt Willis Motors Ltd | Wholesale & retail | 2026 |
| Cypraea Properties Limited | Professional & scientific | 2002 |
| D Tudor Electrical Limited | Construction | 2010 |
| D. Design Engineering Ltd | Professional & scientific | 2023 |
| D.J. Goodall & Co Limited | Professional & scientific | 2003 |
| Dada Club Ltd | Arts & recreation | 2025 |
| Daggeridge Group Ltd | Information & communication | 2025 |
| Daleri UK Ltd | Professional & scientific | 2023 |
| Daresdown Enterprises Limited | Hospitality | 2020 |
| Daresdown Holdings Limited | Financial services | 2020 |
| Darklake View Limited | Real estate | 2023 |
| Darlington Wild LLP | | 2024 |
| Darren Hopkins Consulting Ltd | Wholesale & retail | 2016 |
| Data Comms Direct Limited | Wholesale & retail | 2002 |
| Datelinks Limited | Information & communication | 2004 |